The Rugby World Cup quarter-finals have proved that experience is often overrated with Wales and Australia eliminating older opponents.
Wales and Australia showing the value of youth
The notion that you cannot win anything with kids was dispelled as a myth almost as soon as it so famously left a Scottish football pundit's lips 16 years ago.
Yet, over in the oval-ball code, the penny has still not dropped that experience can be vastly overrated.
South Africa fielded the most capped side in their rich history for their Rugby World Cup quarter-final against Australia.
Even with Radike Samo, the oldest player ever to play Test rugby for Australia, starting at No 8, the average age of the Wallabies was just over 25. By contrast, the Springboks were, per man, more than three years older on average.
Experience is supposed to bring nous, but once that evaporates, a side as elderly as the Springboks are not left with much. They gave up their world title because they played unintelligent rugby.
For much of this World Cup classic in Wellington it was basically David Pocock versus South Africa - a 23-year-old single-handedly taking on a side with 836 caps between them. He won the battle hands down.
Australia are often damned as a side of attacking Fancy Dans, who paper over a leaky defence by dint of their verve going forward.
They play up to it, too, deriding other sides for playing kick-chase or stick-it-up-the-jumper rugby, and making noises about how others are ruining the game by doing so.
But they have always been far savvier defensively than they let on. This was not the first time they have managed to rope-a-dope in a crucial World Cup match.
They were similarly unfancied ahead of their 2003 semi-final against New Zealand. As with this meeting with the Boks, they spent most of that game against the All Blacks in their own territory, yet still left with the spoils.
It does help, of course, in winning the battle between innocence and experience, if you have young players of such searing talent.
Australia have a rare batch at present. They may be young, but they already know how to win tournaments.
Pocock, the open-side flanker, played in the Under 19 World Championship in Dubai in 2006, which Australia won, as did Will Genia and the Faingaa brothers, Saia and Anthony.
Meanwhile, James O'Connor, whose nerveless kick won a semi-final berth for the Australians, was about three years too young for that competition.
Australia are not the only ones to realise the benefit of trusting in youth at this World Cup.
In the first quarter-final, Ireland's golden generation were turning sepia before our eyes, as they were swamped by a Welsh side full of youthful vim.
At the heart of the Welsh effort were Sam Warburton, the captain who turned 23 last week, Toby Faletau, 20, and George North, 19.
Wales and the Wallabies have much still to do if they are going to play a final against each other.
Arguably neither of them should be considered favourites going into their respective semi-finals next weekend.
If they do make it, though, the World Cup final will be the platform for a colossal showdown between the two best open-sides - and perhaps the two best players - in the tournament.
Between them in their quarter-final successes, Warburton and Pocock ran for a combined total of six metres with the ball in hand.
When the Australian player did find himself in clear space against South Africa, he looked totally lost, and threw himself to the turf at the first opportunity. He is far more comfortable down there.
Pocock is half a year older than Warburton, started earlier at Test level and thus has the edge in terms of experience. But, let's be honest - what does that matter, really?